Gemini on Question 1, Sep 20
Is 91 a prime number? Think step by step and then answer "[Yes]" or "[No]".To determine if 91 is a prime number, we can check if it is divisible by any prime numbers smaller than its square root (the square root of 91 is approximately 9.5).
- 1.Check 2: 91 is an odd number (it does not end in 0, 2, 4, 6, or 8), so it is not divisible by 2.
- 2.Check 3: The sum of its digits is 9 + 1 = 10. Since 10 is not divisible by 3, 91 is not divisible by 3.
- 3.Check 5: 91 does not end in 0 or 5, so it is not divisible by 5.
- 4.Check 7: Let's divide 91 by 7.
7 × 10 = 70.
91 - 70 = 21.
7 × 3 = 21.
Therefore, 7 × 13 = 91.
Since 91 can be divided evenly by 7 and 13, it has factors other than 1 and itself. Therefore, it is a composite number, not a prime number.
[No]
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- answered · correct · format ok
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Highlighted: the last [Yes]/[No] bracket, which is the scored answer (No).
To determine if 91 is a prime number, we can check if it is divisible by any prime numbers smaller than its square root (the square root of 91 is approximately 9.5).
1. **Check 2:** 91 is an odd number (it does not end in 0, 2, 4, 6, or 8), so it is not divisible by 2.
2. **Check 3:** The sum of its digits is 9 + 1 = 10. Since 10 is not divisible by 3, 91 is not divisible by 3.
3. **Check 5:** 91 does not end in 0 or 5, so it is not divisible by 5.
4. **Check 7:** Let's divide 91 by 7.
7 × 10 = 70.
91 - 70 = 21.
7 × 3 = 21.
Therefore, 7 × 13 = 91.
Since 91 can be divided evenly by 7 and 13, it has factors other than 1 and itself. Therefore, it is a composite number, not a prime number.
[No]
End of response · 14 lines · 718 characters · sha256 b519fa1cd8a81ffb5c8f906610d8ebf9ed1399819dc3d7c4b3136accd45ea81b